<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Mail
 * @subpackage Storage
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Maildir.php 18951 2009-11-12 16:26:19Z alexander $
 */


/**
 * @see Zend_Mail_Storage_Abstract
 */
require_once 'Zend/Mail/Storage/Abstract.php';

/**
 * @see Zend_Mail_Message_File
 */
require_once 'Zend/Mail/Message/File.php';

/**
 * @see Zend_Mail_Storage
 */
require_once 'Zend/Mail/Storage.php';


/**
 * @category   Zend
 * @package    Zend_Mail
 * @subpackage Storage
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Mail_Storage_Maildir extends Zend_Mail_Storage_Abstract
{
	/**
	 * used message class, change it in an extened class to extend the returned message class
	 * @var string
	 */
	protected $_messageClass = 'Zend_Mail_Message_File';

	/**
	 * data of found message files in maildir dir
	 * @var array
	 */
	protected $_files = array();

	/**
	 * known flag chars in filenames
	 *
	 * This list has to be in alphabetical order for setFlags()
	 *
	 * @var array
	 */
	protected static $_knownFlags = array('D' => Zend_Mail_Storage::FLAG_DRAFT,
                                          'F' => Zend_Mail_Storage::FLAG_FLAGGED,
                                          'P' => Zend_Mail_Storage::FLAG_PASSED,
                                          'R' => Zend_Mail_Storage::FLAG_ANSWERED,
                                          'S' => Zend_Mail_Storage::FLAG_SEEN,
                                          'T' => Zend_Mail_Storage::FLAG_DELETED);

	// TODO: getFlags($id) for fast access if headers are not needed (i.e. just setting flags)?

	/**
	 * Count messages all messages in current box
	 *
	 * @return int number of messages
	 * @throws Zend_Mail_Storage_Exception
	 */
	public function countMessages($flags = null)
	{
		if ($flags === null) {
			return count($this->_files);
		}

		$count = 0;
		if (!is_array($flags)) {
			foreach ($this->_files as $file) {
				if (isset($file['flaglookup'][$flags])) {
					++$count;
				}
			}
			return $count;
		}

		$flags = array_flip($flags);
		foreach ($this->_files as $file) {
			foreach ($flags as $flag => $v) {
				if (!isset($file['flaglookup'][$flag])) {
					continue 2;
				}
			}
			++$count;
		}
		return $count;
	}

	/**
	 * Get one or all fields from file structure. Also checks if message is valid
	 *
	 * @param  int         $id    message number
	 * @param  string|null $field wanted field
	 * @return string|array wanted field or all fields as array
	 * @throws Zend_Mail_Storage_Exception
	 */
	protected function _getFileData($id, $field = null)
	{
		if (!isset($this->_files[$id - 1])) {
			/**
			 * @see Zend_Mail_Storage_Exception
			 */
			require_once 'Zend/Mail/Storage/Exception.php';
			throw new Zend_Mail_Storage_Exception('id does not exist');
		}

		if (!$field) {
			return $this->_files[$id - 1];
		}

		if (!isset($this->_files[$id - 1][$field])) {
			/**
			 * @see Zend_Mail_Storage_Exception
			 */
			require_once 'Zend/Mail/Storage/Exception.php';
			throw new Zend_Mail_Storage_Exception('field does not exist');
		}

		return $this->_files[$id - 1][$field];
	}

	/**
	 * Get a list of messages with number and size
	 *
	 * @param  int|null $id number of message or null for all messages
	 * @return int|array size of given message of list with all messages as array(num => size)
	 * @throws Zend_Mail_Storage_Exception
	 */
	public function getSize($id = null)
	{
		if ($id !== null) {
			$filedata = $this->_getFileData($id);
			return isset($filedata['size']) ? $filedata['size'] : filesize($filedata['filename']);
		}

		$result = array();
		foreach ($this->_files as $num => $data) {
			$result[$num + 1] = isset($data['size']) ? $data['size'] : filesize($data['filename']);
		}

		return $result;
	}



	/**
	 * Fetch a message
	 *
	 * @param  int $id number of message
	 * @return Zend_Mail_Message_File
	 * @throws Zend_Mail_Storage_Exception
	 */
	public function getMessage($id)
	{
		// TODO that's ugly, would be better to let the message class decide
		if (strtolower($this->_messageClass) == 'zend_mail_message_file' || is_subclass_of($this->_messageClass, 'zend_mail_message_file')) {
			return new $this->_messageClass(array('file'  => $this->_getFileData($id, 'filename'),
                                                  'flags' => $this->_getFileData($id, 'flags')));
		}

		return new $this->_messageClass(array('handler' => $this, 'id' => $id, 'headers' => $this->getRawHeader($id),
                                              'flags'   => $this->_getFileData($id, 'flags')));
	}

	/*
	 * Get raw header of message or part
	 *
	 * @param  int               $id       number of message
	 * @param  null|array|string $part     path to part or null for messsage header
	 * @param  int               $topLines include this many lines with header (after an empty line)
	 * @return string raw header
	 * @throws Zend_Mail_Storage_Exception
	 */
	public function getRawHeader($id, $part = null, $topLines = 0)
	{
		if ($part !== null) {
			// TODO: implement
			/**
			* @see Zend_Mail_Storage_Exception
			*/
			require_once 'Zend/Mail/Storage/Exception.php';
			throw new Zend_Mail_Storage_Exception('not implemented');
		}

		$fh = fopen($this->_getFileData($id, 'filename'), 'r');

		$content = '';
		while (!feof($fh)) {
			$line = fgets($fh);
			if (!trim($line)) {
				break;
			}
			$content .= $line;
		}

		fclose($fh);
		return $content;
	}

	/*
	 * Get raw content of message or part
	 *
	 * @param  int               $id   number of message
	 * @param  null|array|string $part path to part or null for messsage content
	 * @return string raw content
	 * @throws Zend_Mail_Storage_Exception
	 */
	public function getRawContent($id, $part = null)
	{
		if ($part !== null) {
			// TODO: implement
			/**
			* @see Zend_Mail_Storage_Exception
			*/
			require_once 'Zend/Mail/Storage/Exception.php';
			throw new Zend_Mail_Storage_Exception('not implemented');
		}

		$fh = fopen($this->_getFileData($id, 'filename'), 'r');

		while (!feof($fh)) {
			$line = fgets($fh);
			if (!trim($line)) {
				break;
			}
		}

		$content = stream_get_contents($fh);
		fclose($fh);
		return $content;
	}

	/**
	 * Create instance with parameters
	 * Supported parameters are:
	 *   - dirname dirname of mbox file
	 *
	 * @param  $params array mail reader specific parameters
	 * @throws Zend_Mail_Storage_Exception
	 */
	public function __construct($params)
	{
		if (is_array($params)) {
			$params = (object)$params;
		}

		if (!isset($params->dirname) || !is_dir($params->dirname)) {
			/**
			 * @see Zend_Mail_Storage_Exception
			 */
			require_once 'Zend/Mail/Storage/Exception.php';
			throw new Zend_Mail_Storage_Exception('no valid dirname given in params');
		}

		if (!$this->_isMaildir($params->dirname)) {
			/**
			 * @see Zend_Mail_Storage_Exception
			 */
			require_once 'Zend/Mail/Storage/Exception.php';
			throw new Zend_Mail_Storage_Exception('invalid maildir given');
		}

		$this->_has['top'] = true;
		$this->_has['flags'] = true;
		$this->_openMaildir($params->dirname);
	}

	/**
	 * check if a given dir is a valid maildir
	 *
	 * @param string $dirname name of dir
	 * @return bool dir is valid maildir
	 */
	protected function _isMaildir($dirname)
	{
		if (file_exists($dirname . '/new') && !is_dir($dirname . '/new')) {
			return false;
		}
		if (file_exists($dirname . '/tmp') && !is_dir($dirname . '/tmp')) {
			return false;
		}
		return is_dir($dirname . '/cur');
	}

	/**
	 * open given dir as current maildir
	 *
	 * @param string $dirname name of maildir
	 * @return null
	 * @throws Zend_Mail_Storage_Exception
	 */
	protected function _openMaildir($dirname)
	{
		if ($this->_files) {
			$this->close();
		}

		$dh = @opendir($dirname . '/cur/');
		if (!$dh) {
			/**
			 * @see Zend_Mail_Storage_Exception
			 */
			require_once 'Zend/Mail/Storage/Exception.php';
			throw new Zend_Mail_Storage_Exception('cannot open maildir');
		}
		$this->_getMaildirFiles($dh, $dirname . '/cur/');
		closedir($dh);

		$dh = @opendir($dirname . '/new/');
		if ($dh) {
			$this->_getMaildirFiles($dh, $dirname . '/new/', array(Zend_Mail_Storage::FLAG_RECENT));
			closedir($dh);
		} else if (file_exists($dirname . '/new/')) {
			/**
			 * @see Zend_Mail_Storage_Exception
			 */
			require_once 'Zend/Mail/Storage/Exception.php';
			throw new Zend_Mail_Storage_Exception('cannot read recent mails in maildir');
		}
	}

	/**
	 * find all files in opened dir handle and add to maildir files
	 *
	 * @param resource $dh            dir handle used for search
	 * @param string   $dirname       dirname of dir in $dh
	 * @param array    $default_flags default flags for given dir
	 * @return null
	 */
	protected function _getMaildirFiles($dh, $dirname, $default_flags = array())
	{
		while (($entry = readdir($dh)) !== false) {
			if ($entry[0] == '.' || !is_file($dirname . $entry)) {
				continue;
			}

			@list($uniq, $info) = explode(':', $entry, 2);
			@list(,$size) = explode(',', $uniq, 2);
			if ($size && $size[0] == 'S' && $size[1] == '=') {
				$size = substr($size, 2);
			}
			if (!ctype_digit($size)) {
				$size = null;
			}
			@list($version, $flags) = explode(',', $info, 2);
			if ($version != 2) {
				$flags = '';
			}

			$named_flags = $default_flags;
			$length = strlen($flags);
			for ($i = 0; $i < $length; ++$i) {
				$flag = $flags[$i];
				$named_flags[$flag] = isset(self::$_knownFlags[$flag]) ? self::$_knownFlags[$flag] : $flag;
			}

			$data = array('uniq'       => $uniq,
                          'flags'      => $named_flags,
                          'flaglookup' => array_flip($named_flags),
                          'filename'   => $dirname . $entry);
			if ($size !== null) {
				$data['size'] = (int)$size;
			}
			$this->_files[] = $data;
		}
	}


	/**
	 * Close resource for mail lib. If you need to control, when the resource
	 * is closed. Otherwise the destructor would call this.
	 *
	 * @return void
	 */
	public function close()
	{
		$this->_files = array();
	}


	/**
	 * Waste some CPU cycles doing nothing.
	 *
	 * @return void
	 */
	public function noop()
	{
		return true;
	}


	/**
	 * stub for not supported message deletion
	 *
	 * @return null
	 * @throws Zend_Mail_Storage_Exception
	 */
	public function removeMessage($id)
	{
		/**
		 * @see Zend_Mail_Storage_Exception
		 */
		require_once 'Zend/Mail/Storage/Exception.php';
		throw new Zend_Mail_Storage_Exception('maildir is (currently) read-only');
	}

	/**
	 * get unique id for one or all messages
	 *
	 * if storage does not support unique ids it's the same as the message number
	 *
	 * @param int|null $id message number
	 * @return array|string message number for given message or all messages as array
	 * @throws Zend_Mail_Storage_Exception
	 */
	public function getUniqueId($id = null)
	{
		if ($id) {
			return $this->_getFileData($id, 'uniq');
		}

		$ids = array();
		foreach ($this->_files as $num => $file) {
			$ids[$num + 1] = $file['uniq'];
		}
		return $ids;
	}

	/**
	 * get a message number from a unique id
	 *
	 * I.e. if you have a webmailer that supports deleting messages you should use unique ids
	 * as parameter and use this method to translate it to message number right before calling removeMessage()
	 *
	 * @param string $id unique id
	 * @return int message number
	 * @throws Zend_Mail_Storage_Exception
	 */
	public function getNumberByUniqueId($id)
	{
		foreach ($this->_files as $num => $file) {
			if ($file['uniq'] == $id) {
				return $num + 1;
			}
		}

		/**
		 * @see Zend_Mail_Storage_Exception
		 */
		require_once 'Zend/Mail/Storage/Exception.php';
		throw new Zend_Mail_Storage_Exception('unique id not found');
	}
}
